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We propose a new approximation-technique to deal with the exact macroscopic integro-differential evolution equations of statistical systems which self-consistently accounts for dissipative effects. Concentrating on one and two point…

High Energy Physics - Phenomenology · Physics 2007-05-23 Herbert Nachbagauer

We analyze the issue of dynamical evolution and time in quantum cosmology. We emphasize the problem of choice of phase space variables that can play the role of a time parameter in such a way that for expectation values of quantum operators…

General Relativity and Quantum Cosmology · Physics 2021-07-05 Alexander Yu. Kamenshchik , Jeinny Nallely Perez Rodriguez , Tereza Vardanyan

I argue that ``good'' mathematical models of spatio-temporal dynamics in two-dimensions require non-local operators in the nonlinear terms. Consequently, the often used Swift-Hohenberg equation requires modification as it is purely local.…

patt-sol · Physics 2008-02-03 A. J. Roberts

The evolution of a quantity, described by a function of space and time, relates the first derivative in time of this function to a spatial operator applied to the function. The initial value of the function at time $t=0$ is given. The…

Mathematical Physics · Physics 2007-05-23 Michelle M. Wyss , Walter Wyss

In quantum physics, disturbance due to a measurement is not negligible. This requires the time parameter $t$ in the Schr\"odinger or Heisenberg equation to be considered differently from a time continuum of experimenter's clock $T$ on which…

Quantum Physics · Physics 2010-11-24 Yoshihiro Sato , Arno R. Bohm

It is argued that the Schr\"odinger equation does not yield a correct description of the quantum-mechanical time evolution of states of isolated (open) systems featuring events. A precise general law for the time evolution of states…

Quantum Physics · Physics 2021-01-05 Jürg Fröhlich , Alessandro Pizzo

With a choice of boundary conditions for solutions of the Schr\"odinger equation, state vectors and density operators even for closed systems evolve asymmetrically in time. For open systems, standard quantum mechanics consequently predicts…

Quantum Physics · Physics 2010-05-25 P. W. Bryant

Non-relativistic quantum mechanics is shown to emerge from classical mechanics through the requirement of a relativity principle based on special transformations acting on position and momentum uncertainties. These transformations keep the…

Quantum Physics · Physics 2007-05-23 Léon Brenig

In an ever-expanding spatially closed universe, the fractional change of the volume is the preeminent intrinsic time interval to describe evolution in General Relativity. The expansion of the universe serves as a subsidiary condition which…

General Relativity and Quantum Cosmology · Physics 2018-06-14 Eyo Eyo Ita , Chopin Soo , Hoi-Lai Yu

We investigate the question of unitarity of evolution between hypersurfaces in quantum field theory in curved spacetime from the perspective of the general boundary formulation. Unitarity thus means unitarity of the quantum operator that…

High Energy Physics - Theory · Physics 2011-08-25 Daniele Colosi , Robert Oeckl

The generalized uncertainty connection between the fluctuations of a quantum observable and its temporal derivative is derived in this study, we demonstrate that the product of an observable's uncertainties and its time derivative is…

Quantum Physics · Physics 2025-08-26 Tarek Yehia

Generalized Gibbs ensembles have been used as powerful tools to describe the steady state of integrable many-particle quantum systems after a sudden change of the Hamiltonian. Here we demonstrate numerically, that they can be used for a…

Strongly Correlated Electrons · Physics 2018-05-02 Florian Lange , Zala Lenarčič , Achim Rosch

The problem of time in canonical quantum gravity remains one of the most significant challenges, primarily due to the "frozen" formalism emerging from the Wheeler-DeWitt equation. Within the ADM formalism, we introduce a novel approach in…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Pradosh Keshav MV

In non relativistic quantum mechanics time enters as a parameter in the Schroedinger equation. However, there are various situations where the need arises to view time as a dynamical variable. In this paper we consider the dynamical role of…

Quantum Physics · Physics 2015-05-14 Y. Strauss

A relativistic collapse model for distinguishable particles is presented. Position and time, for each particle, are the fundamental operators of the theory. The Schr\"odinger equation is of the CSL form, with a Hermitian Hamiltonian and an…

Quantum Physics · Physics 2025-06-10 Daniel J. Bedingham , Philip Pearle

This paper is the third part concluding the introduction of the powerful algebra of the pseudo-observables. In this article will be dealt how to treat the time evolution, and, more in general, the transformations, in the framework of the…

Quantum Physics · Physics 2017-08-18 Edoardo Piparo

Time can be defined as the duration between events. It is irreversible. When used as a variable in quantifying the changing properties of matter, this irreversibility of time is incompatible with Newton's deterministic mechanics and with…

chao-dyn · Physics 2007-05-23 X. de Hemptinne

The spread of the time arrows from the environment to an observed subsystem is followed within a harmonic model. A similarity is pointed out between irreversibility and a phase with spontaneously broken symmetry. The causal structure of…

High Energy Physics - Theory · Physics 2012-06-26 Janos Polonyi

We introduce a `proper time' formalism to study the instability of the vacuum in a uniform external electric field due to particle production. This formalism allows us to reduce a quantum field theoretical problem to a quantum-mechanical…

Quantum Physics · Physics 2010-11-23 Fabian H. Gaioli , Edgardo T. Garcia Alvarez , Mario A. Castagnino

In quantum mechanics, the time evolution of particles is given by the Schr\"odinger equation. It is valid in a nonrelativistic regime where the interactions with the particle can be modelled by a potential and quantised fields are not…

Quantum Physics · Physics 2026-03-24 Martin Plávala , Stefan Nimmrichter , Matthias Kleinmann